1. Field of the Invention
The present invention relates to a portable terminal with imaging capabilities, and particularly to a folding portable terminal with an imaging camera, the folding portable terminal being formed by turnably coupling two casings so as to be opened and closed.
2. Description of Related Art
There are various kinds of conventional portable terminals such as PDAs (Personal Digital Assistants) and cellular phones. Among all the kinds of portable terminals, the cellular phone is most widely used in society. One type of cellular phone is the folding type that joins a display section casing and an operation section casing foldably via hinge joints so that both casings mate with each other. Since such a folding type can make its overall dimensions compact and its display screen relatively big, it widely gains currency in the market. There is also another conventional type of cellular phone with an imaging camera. With this type of cellular phone, still or motion picture transmitting and receiving services have been offered. One example of this type is disclosed in JP-A-2001-320463. This publication teaches that an imaging camera is equipped on the rear of the casing so that the user can pick up with the camera an image of an external object (others) while monitoring it on an LCD (Liquid Crystal Display). Since this configuration places importance on photographing others, it is awkward to photograph the user himself or herself (the self) because the monitor screen cannot be seen by the user.
Another type of folding cellular phone with an imaging camera is disclosed in JP-A-10-65780 and JP-A-11-69214. In this type of folding cellular phone, the imaging camera is mounted rotatably via hinge joints, so that the user can point the imaging camera at both the self and the external object through one-touch operation in such a state that the LCD side casing remains open, thereby photographing the target image while monitoring it on the LCD. This configuration allows for use of video telephone functions realized in such a manner that the user points the imaging camera at himself or herself during a telephone conversation to take and transmit a video picture of himself or herself while displaying a video picture of the conversation partner on the LCD.
Although various types of imaging camera-equipped portable terminals having such a configuration are now in practical use, the camera unit of the imaging camera equipped in each type of portable terminal is just soldered on a circuit board without special consideration for durability against dropping impact.
In the technique described in JP-A-11-69214, a hinge joint or connection portion between two casings is provided only on one side, and this hinge mechanism lowers its torsional rigidity and flexural rigidity important to support the two casings. Further, the cantilevered state of the image camera portion is also vulnerable to deformation-induced damage due to impact from dropping or the like.
The technique described in JP-A-10-65780 is stronger in structure than the technique described in JP-A-11-69214 because two hinge joints are provided at both ends. In this technique, however, since the casing that houses the imaging camera is larger than the outside diameter of the hinge joints, the camera casing first bumps against obstacles in case of dropping the cellular phone. This causes that inertial forces, imposed not only on the camera and the camera casing, but also on the other parts of the cellular phone, are exerted on the camera casing and the hinge joints, thereby running the danger of damaging the camera casing and the hinge joints.